<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>登录</title>
    <!--[if lt IE 9]>
    <script src="./js/html5.js"></script>
    <script src="./js/respond.min.js"></script>
    <![endif]-->
    <!--兼容ie8 html5标签--><!--ie8支持媒体查询-->
    <link rel="stylesheet" href="css/login1.css">
</head>
<body>
<section>
    <div class="container">
        <form class="form-signin" action="index.html">
            <h2 class="form-signin-heading">后台登录</h2>
            <div class="login-wrap">
                <input type="text" class="form-control" placeholder="用户 ID">
                <input type="password" class="form-control" placeholder="用户密码">
                <div class="login-verifiy">
                    <input type="text" class="form-control" placeholder="验证码">
                    <span>1234</span>
                </div>
                <label class="checkbox" style="clear: both">
                    <input type="checkbox" value="remember-me"> 记住我
                    <span> <a href="#" style="color: #337ab7;">忘记密码?</a></span>
                </label>
                <button class=" btn-login " type="submit">提交</button>
            </div>
        </form>
    </div>
</section>
</body>
<script src="js/jquery.js"></script>
<script src="http://cdn.bootcss.com/jquery-placeholder/2.3.1/jquery.placeholder.min.js"></script>
<script type="text/javascript">
    $(function () {
        $('input, textarea').placeholder();
    });
    $(".login-verifiy span").html(MathRand);

    /**
     * @return {string}
     */
    function MathRand() {
        var Num = "";
        for (var i = 0; i < 4; i++) {
            Num += Math.floor(Math.random() * 10);
        }
        return Num;
    }
</script>
</html>